Diaryl guanidine addition products



Patented Oct. 8, 1946 DIARYL GUANIDINE ADDITION PRODUCTS Arnold Rogers Davis, Riverside, Conn., assignor to American Cyanamid Company, New York, 'N. Y., a corporation of Maine No Drawing. Application August 7, 1944, Serial No. 548,497

Claims.

This invention relates to a group of new chemical products. More particularly, the invention relates to a series of chemical compounds which constitute addition products of a diarylguanidine and a zinc salt of a mercaptan or a dithiocarbamic acid.

These new products are variously useful but, in particular, are adapted for use in vulcanization of rubber, both natural and synthetic. Both the diarylguanidines and mercaptans and dithiocarbamic acids are known. These have been previously used in vulcanization, for example, the

diarylguam'dines and the zinc salt of mercaptobenzothiazole, as well as the dithiocarbamates have been used in conjunction with each other to obtain results which could not'be obtained using these agents alone. The present group of new chemical combines both types of agent into a single compound, having the advantage that a plurality of agents need not be used by the industry to obtain the desired results; The present application relates to the new products, per se, vulcanization processes using the same being set forth in my copending application for United States Letters Patent, Serial No. 548,498, filed of even date.

The new compounds of the present invention are most simply described as reaction products which may be designated by the formula AxZn(B)2. A represents such diaryl guanidines as diphenyl guanidine, ditolyl guanidines, particularly the diorthotolyl guanidine, the dixylyl guanidines, dinaphthyl uanidine, and the like. In the present invention :1: represents the integers 1 and 2. The group designated as B may be quite widely varied since Zn(B)2 represents salts of both marcaptans and dithiocarbamic acids. In this group are such compounds as the zinc salts of mercaptobenzothiazole, the dialkyl dithiocarbamic acids such as the dimethyl, diethyl, dibutyl and 'bis-alkoxyalkyl; the alkyl, aryl dithiocar-' bamic acids such as the'N,N-propyl, phenyl and N,N-butyl, phenyl, dithiocarbamic acids and the like. i A

The proportions in which the diaryl guanidine and the zinc salt are combined may be quite widely varied. In general, however, it has been found preferable to use from'one to two mol parts of the diaryl guanidine with one mol part of the zinc salt, The products may be readily produced by heating the reactants to the fusion point and,

the reaction by gentle heating as on a steam bath. Products of the reaction may be either amorphous or crystalline, many ofthem appearing as clear resins and others as clear white crystals. Whichever the form in which the product is obtained it has a fixed analysis, and in the case of the crystalline forms, a definite melting point, indicating that a true chemical compound is formed by the reaction and not simply a complex mixture.

The invention will be more fully illustrated in conjunction with the following examples which are intended to be illustrative only and not by way of limitation. All parts are by weight unless otherwise noted. In these examples the followin abbreviations are used for the sake of simplification:

D. P. G.-diphenyl guanidine D. O. T. G.-di-o-toly1 guanidine D. X. G.--dixylyl guanidine M. B. 'I'.mercaptobenzothiazole D. T. C.dithiocarbamic acid EXAMPLE 1 (D. P. G.)zZn(M. B. T.) 2

199 parts of the zinc salt of mercaptobenzothiazole and 211 parts of diphenyl guanidine were heated together with stirring until they fused at about 110 C. A clear resin formed in a few minutes. The fusion product was held at l00-110 C. for about 15 minutes after which the melt was cooled, crushed, ground and remelted at about C. A clear resin was formed.

EXAMPLE 2 EXAMPLE 3 The process of Example 2 was repeated, using 513 parts of zinc N,N-n-butyl, phenyl dithiocarbamate and 211 parts of diphenylguanidine. As

in Example 2, a clear liquid was formed which give a clear film on cooling. I

(D. P. G.) lZll SSON 3 EXAMPLE 4 (D. P. G.)Zn(M. B. T..)2'

The procedure of Example 1 was repeated, using 199 parts of the zinc mercaptobenz-othiazole and 106 parts, diphenylguanidine. The mass fused at 125-130? C. and after being cooled,

. crushed, and ground, melted at about 130 C.

The product was a light brownish-yellow resin.

EXAMPLE 5 513 parts of zinc butylphenyldithiocarbamate and 211 parts of diphenylguanidine were fused v together for about minutes at 95 C. A substantially water-white resin was formed.

EXAMPLE 6 C2135 czHs 2 The procedure of Example 5 was repeated using 107 parts of dixylylguanidine and '7 3 parts of zinc diethyldithiocarbamate. After about one-half hours heating at 100-105 C. a clear, resinous product was obtained.

EXAMPLE '7 The procedure in Example 6 was repeated using half the quantity of zinc diethyldithiocarbamate. A similar appear resin was obtained.

EXAMPLE 8 534 parts of dixylyl guanidine were added to a solution of 362 parts of zinc diethyldithiocarbamatein benzene at 30 C. The temperature Was raised to 75-78 C. and held for about 40 minutes after which the solution was filtered,-

the filter washed with hot benzene and the washings added to the original filtrate. The filtrate was rapidly evaporated to about one quarter its original volume and then allowed to stand in air at room temperature. No crystals appeared even after long standing. The product is a soft resin. 1

E AMPLE 9 c'2H5ooaH1 (D. P. G.)Z11(SSCN\ C2H5OG3H7 2 297 parts of zinc bis-ethoxypropyldithiocarbamate were fused together at about 100 C. with Optically, the product showscrystals difiering' from either di-o-tolyl guanidine or zinc merc'aptobenzothiazole.

EXAMPLE 11 47.8 parts of di-o-tolyl guanidine were suspended in 500'parts of benzol and 39.8 parts of zinc mercaptobenzothiazole added thereto. Both materials dissolved on'heating to about YB-80 C.,

the temperature being held at this point until about one-half the benzol was evaporated. On

' standing for about one hour, crystals formed and the mass solidified- About 250 parts of ben'zol were added to dissolve the crystals, the solution "was filtered and cooled, crystals separated out,

washed with benzol and dried in air for about 48 hours. The product was ahomogeneous crystal- 211 parts of diphenyl guanidine, for a suficient time to form a clear liquid. On cooling 2. thick light colored paste was formed indicating crystalline growth.

EXAMPL 10 119 parts of.zinc mercaptobenzc mhiazole and 143 parts of di-o-tolyl guanidine were fused together at 125.? 9, to give a clear melt which 'was cooled, crushed a round and aga n-heated at, for about 15 m ites. e ite: wh ch the f r sion product was allowed to stand overnight.

0 togetherz" 3 line mass melting at 152'-153 C. and having a nitrogen content of 12.30% and a sulfur content 1 '.EXAMPLE .2

-The same amountsof material used in EXainple 11 were fused together at 170 C. and heated" at 153-155 Cgu-ntil the melt was clear. amorphous product-was obtained.

7 E A P E 13 -ch as r p ated using 51.3. parts of inc N-p pyl. n nyl dithiocarbajmate and 422 parts of diphenyl guanidine... After .30 minutes of heating, the'solution allowed crystals of the product to form when cooled.

EXAM L 14 A glassy Example 11 was repeated using 39.8partsof zinc Q mercaptobenzothiaz ole and 147.8 parts of dio t ol e yl guanidine 500 parts of benzol. A cleanselution formed after about one-ha-lf hour" at '70: C. Heating was continued for one hour, followed, by filtrationg- On cooling, no crystals 'for m d.

About one-half the solvent was then evaporated.

The crystals forrnegl afterevaporating part ofthe solvent were redissolved in -benzol'an'd recrystal-lv lized. The resultant crystals formed were washed twiceinbenzol and dried at C. forabout' one hour. The crystalline product had a melting point of 15 5157 C; and the following analysis:

N,',%' V 12.74 12.78 s, .1- 14.40 14.60

clarity of the melt; T V

1 EX P E. 1.

. w niafie '11 bitty-l u zlii 2.: 'The product of Example-3 "(DZ 1 (N N butyl, phenyl Di C.) 2 was rfn'ade intof-t'he fol lowing composition by inilli Butyl B (containsisa, z rlo,i1.5% m- Stearioac j f lletex l Accelerator the com hents 5 After curing for 60 minutes at 153 C. the product was found to be a Shore Hardness of 44.

EXAMPLE 17 Vulcanization of Buna S The same accelerator produced in Example v3 was made up into the following composition:

Effect of varying proportions of diaryl guanidine n vulcanization In order to show the distinction between the use of diaryl guanidine in the ratio of l and 2 parts of diaryl guanidine per part of zinc salt, the following compositions were prepared and tested and the results shown in the table were obtained.

Compounds G. R.-S 100 100 Bardol (coal tar softener) 5 Zinc oxide 5 5 E. P. C. black 50 50 Sulfur 2 2 (D. P. G.)zZn(M. B. T02 .89

(From Example 1) D. P. G.Zn(M. B. T02 .90

(From Example 4) 60' cure at 141 0.

Shore hardness 60 61 Mod. at 300% 1,070 755 Tensile 2,610 2,285 Elongation 535 590 Torsional hysteresis K at EXAMPLE 19 Comparison of solvent as. fusion products results are obtained whether the products of the present invention are prepared by fusion or by the solvent process, the compositions shown in the following table were prepared and tested. It will be noted that substantially equivalent results 5 were obtained.

Compounds G. R.-S 100 100 Bardol (coal tar softener) 5 5 Zinc oxide 5 5 10 E. P. C. black 50 50 Sulfur 2 2 (D. O. T. G.)2Zn(M. B. T.)2 (Ex.

14) 0.90 (D. O. T. G.)2Zn (M. B. T02 (Ex. 15 15) 0.90

Cured 55 minutes at 141 C. Shore hardness (30") 61 59 Mod. at 300% 1,150 1,100 Tensile 3,050 2,950 Elongation 580 600 Set at break, 26 26 Torsional hysteresis K at 280 F .168 .174 DeMattra out growth rate mils./kc 33 27 I claim:

1. A reaction product of one to two mol of a diaryl-guanidine and one mol of a zinc salt having the formula Zn(X)z in which X represents a member of the group consisting of the 2. A reaction product of one to two mols of a diaryl-guanidine and one mol of a zinc mercaptobenzothiazole.

3. A reaction product of one to two mols of diphenylguanidine and one mol of zinc mercaptobenzothiazole.

4. A reaction product of one to two mols of di- 0 o-tolyl guanidine and one mol of zinc mercaptobenzothiazole.

5. A reaction product of one to two mols of dixylyl guanidine and one mol of zinc mercaptobenzothiazole.

ARNOLD ROGERS DAVIS.

Certificate of Correction Patent No. 2,409,109. October 8, 1946. ARNOLD ROGERS DAVIS It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Column 4, line 59, Example 15, for 125-104 C. read 125-140" 0.; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Ofiice.

Signed and sealed this 15th day of July, A. D. 1947.

LESLIE FRAZER,

First Assistant Commissioner of Patents. 

